### Install pybars4

Source: https://github.com/up9inc/pybars4/blob/master/readme.md

Install the pybars4 library using pip.

```bash
pip install pybars4
```

--------------------------------

### Basic Template Rendering

Source: https://github.com/up9inc/pybars4/blob/master/readme.md

Demonstrates compiling a template string, defining custom helpers and partials, and rendering the template with provided data. Custom block helpers should accept 'this, options, *args, **kwargs'.

```python
# Get a compiler
from pybars import Compiler
compiler = Compiler()

# Compile the template
source = u"{{>header}}{{list people}}{{firstName}} {{lastName}}{{/list}}"
template = compiler.compile(source)

# Add any special helpers
def _list(this, options, items):
    result = [u'<ul>']
    for thing in items:
        result.append(u'<li>')
        result.extend(options['fn'](thing))
        result.append(u'</li>')
    result.append(u'</ul>')
    return result
helpers = {'list': _list}

# Add partials
header = compiler.compile(u'<h1>People</h1>')
partials = {'header': header}

# Render the template
output = template({
    'people': [
        {'firstName': "Yehuda", 'lastName': "Katz"},
        {'firstName': "Carl", 'lastName': "Lerche"},
        {'firstName': "Alan", 'lastName': "Johnson"}
    ]}, helpers=helpers, partials=partials)

print(output)
```

--------------------------------

### Render Template with Custom Helper

Source: https://github.com/up9inc/pybars4/blob/master/readme.md

Demonstrates how to compile a Pybars template and render it using a custom helper function that returns a `strlist` for unescaped HTML output.

```python
import pybars

source = u"{{bold name}}"

compiler = pybars.Compiler()
template = compiler.compile(source)

def _bold(this, name):
    return pybars.strlist(['<strong>', name, '</strong>'])
helpers = {'bold': _bold}

output = template({'name': 'Will'}, helpers=helpers)
print(output)
```

--------------------------------

### Run All Tests

Source: https://github.com/up9inc/pybars4/blob/master/readme.md

Execute all tests for the Pybars library using the provided test runner script.

```bash
python tests.py
```

--------------------------------

### Debug Pybars Tests

Source: https://github.com/up9inc/pybars4/blob/master/readme.md

Run the test suite with debug output enabled to inspect the Abstract Syntax Tree (AST) and generated Python code.

```bash
python tests.py --debug
```

--------------------------------

### Run Specific Test

Source: https://github.com/up9inc/pybars4/blob/master/readme.md

Execute a single, specific test case within the Pybars test suite.

```bash
python tests.py TestAcceptance.test_subexpression
```

--------------------------------

### Generated HTML Output

Source: https://github.com/up9inc/pybars4/blob/master/readme.md

The expected HTML output after rendering the template with the provided data, helpers, and partials.

```html
<h1>People</h1><ul><li> Yehuda Katz</li><li> Carl Lerche</li><li> Alan Johnson</li></ul>
```

--------------------------------

### Debug Specific Test

Source: https://github.com/up9inc/pybars4/blob/master/readme.md

Run a specific test case with debug output enabled for detailed inspection.

```bash
python tests.py --debug TestAcceptance.test_subexpression
```

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